Thai soldiers stand guard in front of anti-government protesters at the government's temporary office in the suburb of Bangkok on Feb. 19, 2014.

Thousands of anti-government protesters marched through the streets of Bangkok to raise support for their effort to oust Prime Minister Yingluck Shinawatra a day before a vote to elect a new Senate.

The demonstrators, led by former Democrat Party powerbroker Suthep Thaugsuban, marched through the center of Bangkok from their base in Lumpini Park. The ASTV television network estimated as many as 50,000 people joined the rally.

The group has staged a five-month campaign to force Yingluck from office and push for reforms that would blunt the electoral dominance of her brother, former premier Thaksin Shinawatra. Suthep scaled back the protests early this month and lifted a seven-week blockade of Bangkok’s major intersections after the number of supporters at daily rallies dwindled.

The protesters, who derailed the nation’s Feb. 2 general election, have said they won’t disrupt tomorrow’s vote to elect half of Thailand’s 150-member upper house. The Constitutional Court annulled last month’s election after demonstrators disrupted the polls, leaving the Yingluck administration stuck in a caretaker role with limited powers.

“The Senate elections do not determine who forms the government, so there is simply much less at stake,” said Duncan McCargo, a professor of political science at the University of Leeds and senior research affiliate at Columbia University. “Almost half of the Senate is appointed and most appointed senators are broadly in the pro-Democrat camp, so the traditional establishment has been able to exercise much more influence over the Senate than the lower house.”

Corruption charges

The appointed senators are chosen by a committee that includes the heads of the Constitutional Court, Election Commission, National Anti-Corruption Commission, State Audit Commission and a representative of the Supreme Court.

The government has clashed with those so-called independent agencies in recent months, with the Constitutional Court ruling against a bid to change the Senate into a fully elected body and halting the government’s infrastructure spending plan. The NACC is investigating at least 15 cases against Yingluck’s ruling Pheu Thai Party, and the party accused the EC of trying to undermine the February election.

Yingluck is scheduled to appear before the NACC on March 31 to defend herself against charges of dereliction of duty for her role in overseeing the government’s rice subsidy program. The NACC could choose to indict Yingluck, and recommend the Senate move to impeach her.

No justice

The premier yesterday criticized the NACC for not giving her enough time to gather evidence for her defense, and questioned why the case is proceeding so quickly when “progress has not been made in any of the cases made against the previous government.”

Ministers in Yingluck’s government have warned in recent months that her opponents are pursuing a so-called judicial coup, after Suthep’s street protests failed to topple her.

“I have no alternative but to conclude that as far as the examination of evidence and witnesses in this case is concerned, I have not been treated equitably or received any justice,” Yingluck said on her official Facebook page.

The EC will operate 93,618 polling stations nationwide tomorrow, and has asked the police and the army to help ensure the vote isn’t disrupted, Chairman Supachai Somcharoen told reporters today. The commission plans to meet with political parties in early April to discuss a new lower house election, which could be held within 45 to 60 days if there is no political unrest, Supachai said.

Suthep has said protesters will disrupt any general election held before his group’s political changes are enacted, and the Democrats haven’t said whether they will contest a new vote, after boycotting the Feb. 2 polls.

The protesters want to rewrite the political rules to remove what they say is the Shinawatra family’s influence. The past five elections have been won by parties allied with Thaksin, who was ousted in a 2006 coup. The Democrats have not won a national election in more than two decades.